Question

I was wondering if its possible to directly cast objects within a foreach loop.

We have the following two classes were one extends the other:

class Book {};
class ExtendedBook extends Book {};

Now we have an array of Books which I want to loop through, because its a ExtendedBook search I’m sure that all Books are actually Extended Books. Is there a way to directly cast them?

Book [] books = bookSearch.getBooks("extendedBooks");

for (Book book: books){
   ExtendedBook eBook = (ExtendedBook) book;
   ....
}

This involves two steps. First looping through the books and at the second step casting them. Can one do it in one step?

What doesn’t work:

// Directly assign it to a different type
for (ExtendedBook book : books){}

// Directly casting the array
ExtendedBooks [] eBooks = (ExtendedBooks []) books;

// Same goes for trying both in one step
for (ExtendedBook book : (ExtendedBook []) books){}

I know its not a real pain, but keeping the loop shorter would be nice and maybe more readable as you save a dummy variable, which is just used for casting instead of the actual action.

Answer 1

I’m reasonably sure you cannot cast in the loop as you would like.